Technical knowledge about oil leakage of excavator oil cylinder

Reasons for oil leakage of excavator oil cylinder:

Under normal circumstances, the leakage of excavator oil cylinder is divided into two types: internal leakage and external leakage. As long as we observe carefully, we can judge the cause of external leakage. It is more difficult to judge the cause of the internal leakage of the hydraulic cylinder, because we cannot directly observe the internal leakage.

Then, let's briefly talk about the causes of internal leakage and external leakage of excavator oil cylinder.

1. External leakage

The damage of the seal between the extension end of the piston rod and the piston rod is mostly caused by the pulling of the piston cylinder, and it is also caused by aging.

The seal damage of the extension end of the piston rod and the cylinder liner is mostly caused by the long-term use of the seal and the aging of the seal. There are also many cases where the seal is squeezed and damaged by excessive force when the upper end cover is used. There are also many domestic manufacturers of excavator oil cylinder. Unreasonable cause, in most cases, the manufacturer is to save costs.

Cracks in the cylinder inlet and outlet pipe joints can also lead to leakage of the hydraulic cylinder.

Oil leakage caused by defects in the cylinder block or cylinder end caps.

The piston rod is pulled, grooved, pitted, etc.

The deterioration of the lubricating oil causes the temperature of the oil cylinder to rise abnormally, which promotes the aging of the sealing ring.

Oil leakage caused by frequent use beyond the pressure range of the cylinder.

2. Internal leakage

The wear ring on the piston is severely worn, causing friction between the piston and the cylinder liner, and finally straining the cylinder liner, piston and seal.

Long-term use of the seal fails, and the piston seal (mostly U, V, Y-rings, etc.) ages.

The hydraulic oil is dirty, and a large amount of impurities enter the oil cylinder and wear the piston seal to the worst, usually iron filings or other foreign objects.

Precautions for the use of hydraulic cylinders:

Through the above brief introduction, we can find that, in addition to the aging caused by the long-term use of the oil seal, as long as we pay attention to maintenance during our normal work, the problem of oil leakage of the excavator oil cylinder can be avoided. So what do we need to pay attention to when working with excavators? Let's briefly talk about it below.

1. During normal use, we should pay attention to protecting the outer surface of the piston rod to prevent the damage to the seals caused by bumps and scratches. Now some construction machinery oil cylinders will be designed with protective plates. Although there are, we still need to pay attention to prevent bumps and scratches. scratched. In addition, I also need to frequently clean the dust on the oil cylinder dynamic seal dust ring and the exposed piston rod to prevent the difficult-to-clean dirt sticking on the surface of the piston rod from entering the cylinder, thereby causing the piston, cylinder barrel or seal. damage.

2. In normal use, we should also pay attention to frequently check the connection parts such as threads and bolts, and tighten them immediately if they are loose. Because the loosening of these places will also cause the hydraulic cylinder to leak oil, which is well understood by those who are engaged in construction machinery.

3. Lubricate the joint parts frequently to prevent corrosion or abnormal wear in the oil-free state. We also need to pay attention. Especially for some parts with rust phenomenon, we should deal with it in time to avoid oil leakage of hydraulic cylinder caused by rust.

4. During normal maintenance, we should pay attention to replacing the hydraulic oil regularly, cleaning the system filter in time to ensure the cleanliness of the hydraulic oil, which also plays a very important role in prolonging the service life of the excavator oil cylinder.

5. During normal work, we should pay attention to control the temperature of the system, because the oil temperature is too high will reduce the service life of the seal, and the long-term high oil temperature will cause the seal to be permanently deformed, and in severe cases, the seal will fail.

6. Usually, every time we use it, we need to carry out a test run of full extension and full retraction for 3-5 strokes before starting work. The purpose of this is to exhaust the air in the system and preheat each system, so as to effectively avoid the existence of air or water in the system and cause gas explosion in the cylinder block, which will damage the seals and cause leakage in the cylinder, etc. Fault.

7. After each work is completed, we need to pay attention to keeping the big and small arms and buckets in an optimal state, that is, to ensure that all the hydraulic oil in the excavator oil cylinder is returned to the hydraulic oil tank to ensure that the hydraulic cylinder is not under pressure. Because the hydraulic cylinder is subjected to pressure in one direction for a long time, it will also cause damage to the seal.